I´ve run this benchmark for each browser I´ve installed on my N900. Here are the scores:

MircoB
14352 (with flash)
13592 (without flash)

Firefox 1.1
0 (with flash, I had canceled the test, because it doesn´t load the flash test)
23295 (without flash)

Opera 10
21145 (without flash, not supported)

so Firefox is the fastest browser... but the flash support ist quite bad